Toast the fennel and cumin seeds in a small frying pan for 1–2 minutes
Crush with a pestle and mortar and tip into a mixing bowl.
Add the spring onions, chillies, coriander, lime juice, oyster sauce, star anise, vinegar and soy sauce.
Add the prawns and marinate for 10 minutes. Then add grape seed oil to the pan and heat before adding prawns
Stir fry for 3–4 minutes, or until pink and cooked through. Keep warm.
To make the stir-fried greens, heat the oil in a wide, non-stick frying pan over a high heat. Add the pak choi, ginger and soy sauce and cook for 4–5 minutes, or until just wilted.
Serve the greens with the prawns immediately.